Fracture of warm columnar freshwater ice: Thickness effect

The behavior of ice is influenced by numerous variables, including temperature, scale, loading rate, and microstructural properties such as ice type, grain size, and salinity. Surprisingly, the impact of ice thickness, a crucial factor, has been inadequately explored in the existing literature. To address this gap, large-scale experiments were conducted in the Ice and Wave Tank of Aalto University, focusing on the fracture behavior of columnar freshwater ice. The experimental conditions involved ice with temperatures exceeding -0.5°C. 3m x 6m edge-cracked rectangular specimens were loaded monotonically to fracture at rates ranging from 1 to 100 µm/s. Notably, the thickness of the ice specimens varied from 10 to 40 cm. The testing results revealed the following: while thickness had a direct and linear impact on the measured loads, it did not influence the fracture properties. Specifically, the apparent fracture toughness, fracture energy, and crack opening displacements remained unaffected by variations in ice thickness.